In order to measure external parameters, aircrafts are equipped with an ever increasing array of different types of sensors. Some parameters such as rate of climb, altitude and air speed, just to name a few, are usually measured with the use of a plurality of static vent ports located at predetermined locations on the fuselage of an aircraft. These ports may also relate to other functions beside air data testing. In fact, similar ports are also used to test cabin pressure or fuel tanks for example.
Generally speaking, a static vent is a small plate, generally mounted on the side of the fuselage (see FIG. 7). The plate, part of a chamber, comprises a plurality of holes which are connected to the tubes which are linked to the measurement instruments.
Being subjected to repeated cycles of utilisation, the instruments to which these static vents are connected need to be regularly recalibrated. To recalibrate the instruments connected to a static vent, a known pressure is sent through the static vent via an adapter. Then, it is verified that the pressure measured by the instruments is the same as the pressure sent through the static vent. In case of disparity, the instruments are recalibrated.
Nevertheless, in order to obtain a good reading of the calibration pressure, the adapter must be securely attached to the static vent in a sealed manner to prevent any leakage of gas used to calibrate the instruments.
Static vent adapters exist in the art. See for example U.S. Pat. No. 3,017,764, granted to John Gilday. However, the problems with the prior art adapters is that they are designed to fit on static vents with a central hole and preferably a large central hole (i.e. with a diameter greater than 0.062 inch or 1.57 mm). However, in more recent ports, the central hole is either of a reduced diameter (i.e. with a diameter smaller than 0.062 inch or 1.57 mm) or completely inexistent. Also, the static vents of the prior art were generally limited to vacuum testing.
There is therefore a need for a test adapter which obviates the shortcomings of the prior art.